【 Weak current College 】 what HIFI, what are the features of it----Power By 【 China power house network 】

Hi-Fi is the abbreviation of the English High-Fidelity, literal translation is "high fidelity", features: original sound is highly similar to replay sound.

I. What Hi-Fi?

Hi-Fi is we often say "high fidelity", its name is High-Fidelity. It refers to the reproducers can real recording, transmission and playback of the original sound source characteristics, it includes the audio signal of the pitch, loudness, sound and sense of direction, etc. Popular said, Hi-Fi is measured by a playback system can Concert Hall, the scene playing field truly in your playback system reconstruction and kept in the concert hall in biphenyls and listen to the music of realistic and immersive.

Second, Hi-Fi.

You may not find Hi-Fi, first of all computer equipment is excellent, it is not just a sound card, speakers, from the power supply to the drive and the hard drive to the motherboard requires a good audio performance. The requirements for a variety of accessories combine computer a bit more difficult it is, so that computer playback system can really achieve Hi-Fi high definition standard really is, we usually play in the computer standards better playback system called Hi-Fi or Hi-Fi, and professional audio equipment, will make your vegetables and turnip can not be pulled into the same length.

For computer playback systems in the whole, the same routine in our use of high-fidelity sound system just as it must, in the frequency response, signal to noise ratio, sensitivity, isolation, and transient response, harmonic distortion, directional, reached a high level. Of course this just and accessories equipment itself, and the sound player software, sound card drivers, DirectX * whether powerful functionality, and so on all have a lot to do and ask them to be in good equipment level and work on the basis of further on sound signal to make the necessary modification, processing, reproduction of sound not only real, but also to get a certain amount of retouching and landscaping, it will be better able to meet the vast numbers of the subjective listening to at the hearing on special needs. So after reasonable modification of Hi-Fi-fidelity playback system put out of the original audio, and even the scene than in concert hall listening to a higher level, the more delicate.

III. evaluation of the Hi-Fi.

A computer with Hi-Fi quality high-fidelity playback system, typically with 20Hz-20KHz frequency range, less than 0.5% harmonic distortion, 90-110 of about-to-noise ratio, etc.

Personal computer you want to evaluate a Hi-Fi audio playback system, should determine the playback quality of subjective standard and objective criteria set out in two ways. So what is the evaluation of the objective standard computer Hi-Fi? it mainly refers to the physical quantities under a variety of sounds to be compared, as in the rooms by the speaker or headphone replay of sound field and program source (CD, etc.) of the sound field indicators fully or basically the same, we can call the computer playback systems meet or have or basic close objective Hi-Fi-fidelity standards. While the subjective standard? subjective standard of Hi-Fi, high fidelity is based on listening to the auditory characteristics, on the audio signal processing for some reasonable, so that we feel that the speakers or headset issue of sound field and in the acoustic field have the same feeling of being there, clearly, a subjective standard would be equipment level, listen to emotions, tastes, habits, culture, psychology, on the same computer for playback system maybe different people will have different evaluation. But this is normal, because playback system ultimately people oriented. This shows the existing objective indicators on the playback device of physical quantities measurement technology, is not sufficient to indicate that all things, and subjective evaluation of listen sometimes very inconsistent. Therefore, the playback quality Hi-Fi objective standards and subjective criteria there are contradictions between both, and unity. The author believes, for high-fidelity playback Hi-Fi computer system should be based on objective equipment on the basis of a physical quantity, in order to achieve the most listen to confirm that the standard of subjective reality, after all, the playback system ultimately will sound playback for everyone to hear, so our daily on a computer for playback system of evaluation should be to everyone's subjective criteria, rather than a factory for boring objective physical data.

On the computer of the objective criteria for evaluation of main technical performance indicators are: frequency response, signal to noise ratio, harmonic distortion, intermodulation distortion, phase distortion, transient response, transient intermodulation distortion, channel separation, dynamic range and sensitivity, damping characteristics, damping coefficient and impedance characteristics, point to properties, and so on. For these indicators, we can do something about